In-plane field type liquid crystal display device with delta arrangement of three primary color pixels

ABSTRACT

A so-called in-plane electric field type color liquid crystal display device employs the following configuration in order to minimize smear. Groups of row-direction arrayed unit pixels are staggered one-half pitch of the unit pixels from the adjacent row-direction arrayed unit pixel groups. Three adjoining unit pixels are selected from two adjacent row-direction arrayed unit pixel groups so that they straddle these two unit pixel groups, and the three selected adjoining unit pixels are assigned three primary colors respectively.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to a color liquid crystal display deviceand more particularly to a color liquid crystal display device generallycalled an in-plane field type.

(2) Description of the Prior Art

The color liquid crystal display device, generally called in-plane fieldtype, has two transparent substrates arranged opposite each other with aliquid crystal layer interposed therebetween and also includes pixelelectrode, or display electrodes, and counter electrodes, or commonelectrodes arranged on the liquid crystal layer side of at least one ofthe two transparent substrates at locations corresponding to each unitpicture element or pixel. In this construction, the color liquid crystaldisplay device changes a light transmissivity or transmittance of theliquid crystal layer by an electric field applied between the pixelelectrode and the counter electrode whose component is almost parallelto the transparent substrate surfaces.

Such a color liquid crystal display device has come to be known for awide viewing angle characteristics, a capability that enables a viewerto recognize images clearly even when he or she looks at the displaysurface from a wide viewing angle.

In a liquid crystal display device using the active matrix system, theunit pixels are respectively provided with switching elements. A countervoltage, which is a constant voltage or an AC voltage, is applied to thecounter electrodes through a counter signal line common to a group ofunit pixels arranged in a row direction. The pixel electrodes receive avideo signal, which comes from a video signal line, common to a group ofunit pixels arranged in a column direction, through the switchingelements that are turned on by a scan signal from a scan signal linecommon to the row of unit pixels.

In this case, the scan signal lines, the video signal lines and thecounter signal lines are all formed virtually linear and three adjoiningunit pixels of a group arranged in the row direction (the direction inwhich the scan signal line extends) are assigned with three primarycolors respectively.

That is, three adjoining unit pixels are regarded as a single unit pixelfor color display.

Features of the in-plane field type liquid crystal display device havebeen disclosed in, for example, Japanese Application Publication No. Hei5-505247 (PCT/WO91/10936), and Japanese Patent Publication No.21907/1988 (JP-B-63-21907).

SUMMARY OF THE INVENTION

It has been found, however, that the color liquid crystal display devicewith the above configuration is apt to produce so-called smears.

Our investigation into this problem has produced the following findings.

While the pixel electrodes supplied with the video signal (voltage)should ideally produce, with respect to the counter electrodes, anelectric field corresponding to the video signal, they also generateunwanted electric fields with respect to the counter electrodes becauseof the video signal lines arranged close to these electrodes. Smearsresulting from such a phenomenon are called vertical smears, which havebeen found to become more salient as the intervals between theparallelly arranged video signal lines decrease.

Each of the counter signal lines extending in the row direction crossesa very large number of video signal lines running in the columndirection with an interlayer insulation film interposed therebetween.Capacitance generated at these intersecting points and the resistancesof the counter signal lines themselves cause the voltage waveform to beincreasingly dull from the voltage supply end of the counter signallines toward the other end, resulting in so-called horizontal smears.

The present invention has been accomplished under these circumstancesand its objective is to provide a color liquid crystal display devicecapable of suppressing smears significantly.

Representative aspects of the present invention may be brieflysummarized as follows.

The color liquid crystal display device of this invention comprises:opposing transparent substrates with a liquid crystal layer interposedtherebetween; a pixel electrode and a counter electrode formed on theliquid crystal layer side of at least one of the transparent substratesin an area corresponding to each of unit pixels; scan signal lines eachcommon to one group of row-direction arrayed unit pixels; switchingdevices turned on by a scan signal supplied to the associated scansignal line; video signal lines each common to one group ofcolumn-direction arrayed unit pixels and used to supply a video signalto the associated pixel electrodes; and counter signal lines each commonto one group of row-direction arrayed unit pixels and used to apply acounter voltage to the associated counter electrodes; wherein a lighttransmittance of the liquid crystal layer is changed by an electricfield generated between the pixel electrode supplied with the videosignal and the counter electrode at the counter voltage, the electricfield having components almost parallel to the transparent substratesurface; wherein the groups of row-direction arrayed unit pixels areeach staggered one-half pitch of the unit pixels from the adjacentgroups, and three adjoining unit pixels selected from adjacent groups ofrow-direction arrayed unit pixels so that they straddle these adjacentgroups are assigned three primary colors respectively.

Because the color liquid crystal display device has the configurationdescribed above, the three unit pixels function as a single combinedcolor pixel. A predetermined number of combined color pixels arearranged in a row, and thus it is possible to reduce the number of unitpixels and therefore increase the interval between the adjacent videosignal lines.

This allows the distance between the video signal line and the counterelectrode in each of the unit pixels driven by the video signal line tobe increased. This in turn makes it possible to suppress the electricfield produced by the video signal line, the cause of the smear(vertical smear).

The reduction in the number of video signal lines reduces thecapacitances produced at the intersections between the row-directionextending counter signal lines and the video signal lines. This in turnreduces the dullness of voltage waveforms of the counter signal linefrom the voltage supply end toward the other end, thus suppressing thesmear (horizontal smear).

It is therefore possible to provide a color liquid crystal displaydevice that can reduce the smear significantly.

The foregoing and other objects, advantages, manner of operation andnovel features of the present invention will be understood from thefollowing detailed description when read in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view showing an essential portion of one embodiment ofthe liquid crystal display device according to the present invention;

FIG. 2 is a schematic diagram showing the configuration of oneembodiment of the drive circuit for the liquid crystal display deviceaccording to this invention;

FIG. 3 is a cross section taken along the line III--III of FIG. 1;

FIG. 4 is a cross section taken along the line IV--IV of FIG. 1;

FIG. 5 is a cross section taken along the line V--V of FIG. 1;

FIG. 6 is an explanatory diagram showing the relation between thedirection of an electric field applied in the liquid crystal and therubbing direction of the orientation film;

FIG. 7 is an explanatory diagram showing the arrangement of colorfilters in the configuration of FIG. 1;

FIG. 8 is a plan view showing an essential portion of another embodimentof the liquid crystal display device according to this invention;

FIG. 9 is an explanatory diagram showing the arrangement of three unitpixels that together constitute a single combined color pixel in theconfiguration of FIG. 8;

FIG. 10 is a plan view showing an essential portion of still anotherembodiment of the liquid crystal display device according to thisinvention; and

FIG. 11 is an explanatory diagram showing the arrangement of colorfilters in the configuration of FIG. 10.

DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred embodiments of the liquid crystal display device of thisinvention will be described with reference to the accompanying drawings.

First, the outline of the liquid crystal display device of the so-calledin-plane field type, the subject of this invention, is explained.

Shown in FIG. 2 is a liquid crystal display device 1 which has twoopposing transparent substrates with a liquid crystal interposedbetween. On the liquid crystal side of one transparent substrate 1A areformed scan signal lines 2 that extend in an x direction (row direction)and are arranged in a y direction (column direction). Isolated from thescan signal lines 2, video signal lines 3 extend in the y direction andare arranged in the x direction.

The video signal lines 3, though shown to be linear in the figure, maybe formed meandering, as in other embodiment described later.

Rectangular areas enclosed by the scan signal lines 2 and the videosignal lines 3 are where unit pixels are formed. These unit pixels arearranged in matrix to form a display surface.

The configuration of these unit pixels will be explained later. In theso-called in-plane field type, counter signal lines 4 each common for agroup of unit pixels arranged in the x direction are provided and eachof these counter signal lines 4 is connected to an AC voltage.

The counter signal lines 4 may also be provided on the liquid crystalside surface of another transparent substrate 1B opposite thetransparent substrate 1A where the scan signal lines 2 are provided.

The liquid crystal display device 1 has a vertical scan circuit 5 and avideo signal drive circuit 6 as external circuits. The vertical scancircuit 5 supplies a scan signal (voltage) successively to theindividual scan signal lines 2. In synchronism with this timing, thevideo signal drive circuit 6 supplies a video signal (voltage) to thevideo signal lines 3 successively.

The scan signal lines 2 are connected to an AC voltage of the sameamplitude as the counter signal lines 4 when the scan signal lines 2 arenot selected.

The vertical scan circuit 5 and the video signal drive circuit 6 aresupplied from a liquid crystal drive power circuit 7 and are also givenimage information from a CPU 8 through a controller 9 that divides theimage information into display data and control signals.

The voltage applied to the counter signal lines 4 is also supplied bythe liquid crystal drive power circuit 7.

Embodiments of the unit pixels used in the liquid crystal display device1 of the above configuration will be described in the following.

Embodiment 1

FIG. 1 is a plan view showing the arrangement of the unit pixels on thetransparent substrate 1A. A cross section taken along the line III--IIIof FIG. 1 is shown in FIG. 3; a cross section along the line IV--IV isshown in FIG. 4; and a cross section along the line V--V is shown inFIG. 5.

As shown in FIG. 1, on the main surface of the transparent substrate 1Athere are formed linearly extending counter signal lines 4 and scansignal lines 2. These counter signal lines 4 and scan signal lines 2 arealternated with each other and arranged parallel to each other. Theinterval between a given counter signal line 4 and a scan signal line 2located on the side of -y direction (on the lower side in the drawing)is set large, whereas the interval between the same counter signal line4 and a scan signal line 2 located on the side of +y direction (on theupper side in the drawing) is set small.

An insulating film 18 is formed over a virtually whole area of thesubstrate covering the scan signal lines 2 and the counter signal lines4 (see FIG. 3). Over this insulating film 18 are formed video signallines 3 that extend in the y direction. That is, the insulating film 18functions as an interlayer insulating film for the scan signal lines 2and the counter signal lines 4 with respect to the video signal lines 3.

The adjoining video signal lines 3 are spaced at the same intervals andextend parallel to a counter signal line 4 in the x direction and thenin the -y direction crossing the counter signal line 4 and scan signalline 2, after which they extend parallel to a scan signal line 2 in the-x direction and then in the -y direction crossing the counter signalline 4 and scan signal line 2. The video signal lines 3 extend in thiszigzag manner.

Hence, in a case where regions enclosed by the largely-spaced countersignal lines 4 and scan signal lines 2 and by the adjacent video signallines 3 practically constitute unit pixel areas, a group of unit pixelslined in the x direction is staggered one-half pitch of the unit pixelsfrom the adjacent group of the x-direction arrayed unit pixels.

In the area of such a unit pixel, a thin film transistor TFT (enclosedby a dashed circle) is formed in a part of each scan signal line 2. Thethin film transistor TFT is made of a MIS(Metal-Insulator-Semiconductor) transistor which turns on when a scansignal is supplied to the underlying scan signal line 2, with a part ofthe scan signal line 2 working as a gate of the transistor and theinsulating film 18 as a gate insulating film.

A drain pad 3A of the thin film transistor TFT is formed integral withthe video signal line 3 located on the -x direction side (on the leftside in the figure) and a source pad 10A is formed integral with a pixelelectrode 10.

The pixel electrode 10 extends from the source pad 10A in the +ydirection and then runs in the +x direction over the counter signal linewith the insulating film 18 interposed therebetween, after which itextends in the -y direction, forming a U-shaped contour.

Between the pixel electrodes 10 running in the y direction there isformed a counter electrode 11 that extends in the y direction. Thecounter electrode 11 is formed integral with the counter signal line 4at a point under the insulating film 18.

The U-shaped pixel electrode 10 generates a storage capacitance Cstg(enclosed by a dashed ellipse in the figure) between its x-directionextending portion and the underlying counter signal line 4, with theinsulating film 18 (which functions as a dielectric film) interposedbetween the pixel electrode and the counter signal line. The storagecapacitance Cstg, when the thin film transistor TFT turns off, stores avideo signal in the pixel electrode 10.

The surface of the transparent substrate 1A with the above constructionis coated with a silicon nitride protective film 12, which is furthercovered with an orientation film 13 of polyimide (see FIG. 3).

In each of the unit pixels constructed in this way, when a scan signalis supplied to the scan signal line 2, the corresponding thin filmtransistor TFT is turned on to supply a video signal from the videosignal line to the pixel electrode 10 through the drain pad 3A andsource pad 10A of the thin film transistor TFT.

Since the counter electrode 11 opposing the pixel electrodes 10 isconnected to AC voltage, an electric field with its components almostparallel to the main surface of the transparent substrate 1A is formedbetween these electrodes, changing the light transmittance of the liquidcrystal disposed between them.

FIG. 3 is a cross section taken along the line III--III of FIG. 1 andillustrates the electric field E generated in the liquid crystal LC. Inthis cross section, the other transparent substrate 1B is shownassembled through the liquid crystal LC. On the liquid crystal sidesurface of the transparent substrate 1B in the area of the unit pixel isformed a color filter 14, which covers a part of a black matrix 15 thatencloses the unit pixel area along the periphery. A protective film 16is formed over the color filter 14 and the black matrix 15. Over thesurface of the protective film 16 is formed an orientation film 17 madefrom polyimide.

A gap between the opposing transparent substrates 1A and 1B is 4.1 μm,and the liquid crystal LC interposed between them is a nematic type thathas a positive dielectric anisotropy Δε of 7.3 (1 kHz) and arefractivity anisotropy Δn of 0.073 (589 nm, 20° C.). FIG. 6 shows therubbing direction of the orientation films 13, 17 with respect to thedirection of the electric field E generated between the pixel electrode10 and the counter electrode 11. The angle Φ between these directions isset at 85°. Further, as shown in FIG. 3, polarizing films 21, 22 areformed over the surfaces of the transparent substrates 1A, 1B on theside opposite the liquid crystal LC. The polarized light transmissionaxis of one of the polarizing films is parallel to the angle Φ of therubbing direction of the orientation film and the polarized lighttransmission axis of the other polarizing film is perpendicular to thefirst axis.

FIG. 4 shows the cross section taken along the line IV--IV of FIG. 1.This is a cross section of the thin film transistor TFT that uses a partof the scan signal line 2 as its gate. Over a part of the scan signalline 2 is formed a semiconductor layer 19 of amorphous silicon, with theinsulating film 18 interposed between. On the semiconductor layer 19,the drain pad 2A and the source pad 10A are formed, spaced from eachother.

In this case, as explained earlier, the drain pad 3A is formed integralwith the video signal line 3 and the source pad 10A with the pixelelectrode 10.

FIG. 5 shows the cross section taken along the line V--V of FIG. 1,showing the storage capacitance Cstg formed between the pixel electrode10 and the counter signal line 4, with the insulating film 18 as thedielectric film.

FIG. 7 explains the use of colors of the color filters 14 that areformed on the transparent substrate 1B at locations corresponding to theunit pixels formed on the transparent substrate 1A, with the liquidcrystal LC interposed between the two substrates.

In the figure, a unit pixel with a red (R) color filter in a given groupof x-direction arrayed unit pixels, for example, works together with twoadjacent unit pixels having green (G) and blue (B) color filtersrespectively that are included in the next x-direction arrayed unitpixel group, one row up or down in the figure, to form a single combinedcolor pixel. That is, three adjoining unit pixels, which are selectedfrom the adjacent groups of x-direction arrayed unit pixels so that theystraddle these adjacent groups, are assigned three primary colors.

In vertical stripe configuration of prior art, for example, 10.4 inchdiagonal display device has 640×3 unit pixels with 0.11 mm pitch inx-direction, and 480 unit pixels with 0.33 mm pitch in y-direction. Inthis configuration, a pitch in x-direction of a unit pixel is set onethird of a pitch in y-direction.

However, in this embodiment of delta configuration, five inch diagonaldisplay device has been realized by comprising 240 unit pixels with0.423 mm pitch in x-direction, and 234 unit pixels with 0.319 mm pitchin y-direction. To be more specific, the display image is still good andwell recognizable even if a pitch in x-direction of a unit pixel is setmore than one third of a pitch in y-direction. This feature of thedisplay image is especially suitable for television or navigation usage.In general, a pitch in x-direction of a unit pixel is set equal to apitch in y-direction, or within ±60% of a pitch in y-direction.

With the liquid crystal display device of the above embodiment, becausea predetermined number of combined color pixels, each made up of threeunit pixels, are arranged in a row, the number of unit pixels can bereduced, allowing the intervals between the adjacent video signal linesto be increased.

This means that it is possible to suppress the noise field of anelectric field produced by the video signal line 3, which enters intothe area between the counter electrode and the pixel electrode, thussuppressing the cause of the smear (vertical smear).

The reduction in the number of video signal lines 3 reduces thecapacitances produced at the intersections between the row-directionextending counter signal lines 4 and the video signal lines 3, with theinterlayer insulating film interposed between these lines. This in turnreduces the dullness of voltage waveforms of the counter signal linefrom the voltage supply end toward the other end, thus suppressing thesmear (horizontal smear).

Therefore, it is possible to provide a color liquid crystal displaydevice that can reduce the smear significantly.

Embodiment 2

FIG. 8 corresponds to FIG. 1 and the members have the same functions asthose of FIG. 1 with like reference numbers.

What differs from the configuration of FIG. 1 is that the unit pixelsarrayed in the y direction and connected to the video signal line 3through the thin film transistors TFT are arranged on each side of thevideo signal line 3 alternately.

While the configuration of FIG. 1 requires video signals of differentcolors to be supplied to a single video signal line, this configurationmakes it possible to supply the video signals of the same color at alltimes.

This simplifies the configuration of the controller 9, offering theadvantage of reducing the cost of members in addition to the advantagesof the Embodiment 1.

In this case also, as shown in FIG. 9 which corresponds to FIG. 8, threeadjoining unit pixels are selected from adjacent groups, arranged in thex direction, of the y-direction arrayed unit pixels so that theystraddle these groups. The selected three adjoining unit pixels areprovided with red (R), green (G) and blue (B) color filtersrespectively.

Embodiment 3

FIG. 10 corresponds to FIG. 1 and the members having identical referencenumbers with those of FIG. 1 have the same functions.

The point in which this embodiment differs from the configuration ofFIG. 1 is the video signal line 3. The vide signal line is formed linearand the column-direction arrayed unit pixels that are commonly connectedto the associated video signal line are successively positioned at thecenter of and on one side of the video signal line alternately.

In this case too, the x-direction arrayed unit pixel groups arestaggered one-half pitch of the unit pixels from the adjacent groups.

Hence, the unit pixels through the center of which the video signal line3 runs have each formed on both sides of the video signal line a pixelelectrode 10 to which a video signal is supplied through a thin filmtransistor TFT and a counter electrode 11 for generating an electricfield between it and the pixel electrode 10.

With this configuration, as shown at (b) of the figure that correspondsto (a), it is possible to put the unit pixels that make up a combinedcolor pixel (shaded with diagonal lines) in the arrangement of FIG. 1even when the video signal line 3 is formed linear.

Because the interval between the counter signal line 4 and the scansignal line located on the +y direction side of the counter signal linecan be reduced, this embodiment has the advantage of improving theaperture ratio in addition to the advantages of the Embodiment 1.

FIG. 11 is an explanatory diagram showing the arrangement of colorfilters (R, G, B) of the unit pixels in the above configuration.

It is of course possible, in Embodiment 1, 2 and 3, to provide thecounter signal lines 4 and the counter electrodes 11 on the liquidcrystal side surface of the transparent substrate 1B. In this case, theauxiliary capacitance functions as an added capacitance produced betweenthe pixel electrode 10 and the previous scan signal line 2 with theinsulating film 18 working as a dielectric.

As can be seen from the above description, the present invention canprovide a color liquid crystal display device that can reduce smearsignificantly.

Also, this invention is applicable for an in-plane field type devicewithout color filter for displaying a black and white image.

What is claimed is:
 1. A liquid crystal display device comprisingopposing two substrates, at least one which is transparent, a liquidcrystal layer interposed therebetween, a pixel electrode and a counterelectrode formed on at least one of the two substrates in an areacorresponding to each of unit pixels, scan signal lines each common toone group of row-direction arrayed unit pixels, switching devices turnedon by a scan signal supplied to the associated scan signal line, videosignal lines each common to one group of column-direction arrayed unitpixels and used to supply a video signal to the associated pixelelectrodes;wherein a light transmittance of the liquid crystal layer ischanged by an electric field generated between pixel electrode and thecounter electrode, the electric field having components almost parallelto the transparent substrate surface; wherein the two groups ofrow-direction arrayed unit pixels are each staggered one half-pitch ofthe unit pixels from the adjacent groups; wherein the scan signal linesand the counter signal lines are formed linear and the video signallines extend in a zigzag and are located on one side of each group ofcolumn-direction arrayed unit pixels, each video signal line beingcommon for one group of column-direction arrayed unit pixels; andwherein the column-direction arrayed unit pixels connected through thinfilm transistors to the associated video signal line are arranged oneach side of the video signal line alternately.
 2. A liquid crystaldisplay device comprising opposing two substrates, at least one which istransparent, a liquid crystal layer interposed therebetween, a pixelelectrode and a counter electrode formed on at least one of the twosubstrates in an area corresponding to each of unit pixels, scan signallines each common to one group of row-direction arrayed unit pixels,switching devices turned on by a scan signal supplied to the associatedscan signal line, video signal lines each common to one group ofcolumn-direction arrayed unit pixels and used to supply a video signalto the associated pixel electrodes, and counter signal;wherein a lighttransmittance of the liquid crystal layer is changed by an electricfield generated between pixel electrode and the counter electrode, theelectric field having components almost parallel to the transparentsubstrate surface; wherein the two groups of row-direction arrayed unitpixels are each staggered one half-pitch of the unit pixels from theadjacent groups; and wherein the scan signal lines are formed linear,and the video signal lines extend linearly in such a way that thecolumn-direction arrayed unit pixels of each group are successivelypositioned at the center of and on one side of the video signal linealternately, each video signal line being common for one group ofcolumn-direction arrayed units pixels.
 3. A color liquid crystal displaydevice according to claim 2, wherein the unit pixels through the centerof which the video signal line passes each have a counter electrode anda pixel electrode formed on both sides of the video signal line, and anelectric field having components almost parallel to the transparentsubstrate surface is generated between the counter electrode and thepixel electrode supplied with a video signal through a thin filmtransistor to change a light transmittance of the liquid crystal layer.4. A liquid crystal display device according to claim 1, 2 or 3, whereinthree adjoining unit pixels selected from the adjacent groups ofrow-direction arrayed unit pixels are arranged to straddle the adjacentgroups and are assigned three primary colors respectively.
 5. A liquidcrystal display device comprising:a pair of substrates, at least one ofwhich is transparent; a liquid crystal layer interposed between saidpair of substrates; at least one polarizer in optical relationship withsaid liquid crystal layer; scan signal lines formed in a row-directionover one substrate of said pair of substrates; other lines formed in arow-direction over said one substrate; video signal lines formed oversaid one substrate and crossed by said scan signal lines with aninsulating layer therebetween, each of said video signal lines includingat least first and second electrically connected portions, wherein saidfirst portions extend in a column-direction, and said second portionsare formed inside areas between outer edges of said scan signal linesaway from said other lines and outer edges of said other lines away fromsaid scan signal lines in a plan view; a plurality of unit pixels formedby adjoining said video signal lines and said scan signal lines, saidscan signal lines each common to one group of row-direction arrayed unitpixels of said plurality of unit pixels, and said video signal lineseach common to one group of column-direction arrayed unit pixels of saidplurality of unit pixels, wherein the groups of row-direction arrayedunit pixels are each staggered one-half pitch of the unit pixels fromthe adjacent groups; and each of said plurality of unit pixels comprisesa switching element connected to one of said video signal lines, atleast a pixel electrode connected to said switching element, at least acounter electrode formed over said one substrate so that a lighttransmittance of said liquid crystal display device is changed by anelectric field generated between said pixel electrode and said counterelectrode, said electric field having a component substantially parallelto a surface of said liquid crystal layer.
 6. A liquid crystal displaydevice comprising:a pair of substrates, at least one of which istransparent; a liquid crystal layer interposed between said pair ofsubstrates; at least one polarizer in optical relationship with saidliquid crystal layer; scan signal lines formed in a row-direction overone substrate of said pair of substrates; counter signal lines formed ina row-direction over said one substrate; video signal lines formed oversaid one substrate and crossed by said scan signal lines with aninsulating layer therebetween, each of said video signal lines includingat least first and second electrically connected portions, wherein saidfirst portions extend in a column-direction, and said secondportions-are formed inside areas between outer edges of said scan signallines away from said counter signal lines and outer edges of saidcounter signal lines away from said scan signal lines in a plan view; aplurality of unit pixels formed by adjoining said video signal lines andsaid scan signal lines, said scan signal lines each common to one groupof row-direction arrayed unit pixels of said plurality of unit pixels,said counter signal lines each common to one group of row-directionarrayed unit pixels of said plurality of unit pixels, and said videosignal lines each common to one group of column-direction arrayed unitpixels of said plurality of unit pixels; wherein the groups ofrow-direction arrayed unit pixels are each staggered one-half pitch ofthe unit pixels from the adjacent groups; and each of said plurality ofunit pixels comprises a switching element connected to one of said videosignal lines, at least a pixel electrode connected to said switchingelement, at least a counter electrode connected to one of said countersignal lines so that a light transmittance of said liquid crystaldisplay device is changed by an electric field generated between saidpixel electrode and said counter electrode, said electric field having acomponent substantially parallel to the surface of said liquid crystallayer.
 7. A liquid crystal display device according to claim 6, whereineach of said second portions of video signal lines is separated with aspace from said scan signal lines and said counter signal lines in aplan view.
 8. A liquid crystal display device according to claim 6,wherein at least two counter electrodes are connected to one of saidcounter signal lines in each of said unit pixels, and said firstportions of said video signal lines are positioned between two counterelectrodes in adjoining unit pixels.
 9. A liquid crystal display deviceaccording to claim 8, wherein at least said counter electrodes and saidpixel electrode extend in a column-direction.
 10. A liquid crystaldisplay device according to claim 6, wherein the column-directionarrayed unit pixels are connected through thin film transistors to theassociated video signal line are arranged on one side of the videosignal line.
 11. A liquid crystal display device according to claim 6,wherein the column-direction arrayed unit pixels are connected throughthin film transistors to the associated video signal line and arearranged on each side of the video signal line alternately.
 12. A liquidcrystal display device according to claim 6, wherein three adjoiningunit pixels selected from the adjacent groups of row-direction arrayedunit pixels are arranged to straddle the adjacent groups and areassigned three primary colors respectively.
 13. A liquid crystal displaydevice comprising:a pair of substrates, at least one of which istransparent; a liquid crystal layer interposed between said pair ofsubstrates; at least one polarizer in optical relationship with saidliquid crystal layer; scan signal lines formed in a row-direction overone substrate of said pair of substrates; counter signal lines formed ina row-direction over said one substrate; video signal lines formed oversaid one substrate and crossed by said scan signal lines with aninsulating layer therebetween, and extended in a column-direction; and aplurality of unit pixels formed by adjoining said video signal lines andsaid scan signal lines, said scan signal lines each common to one groupof row-direction arrayed unit pixels of said plurality of unit pixels,and said video signal lines each common for one group of columndirection arrayed unit pixels, wherein said column-direction arrayedunit pixels are successively positioned at the center of and on one sideof one of said video signal lines alternately, and wherein the groups ofrow-direction arrayed unit pixels are each staggered one-half pitch ofone unit pixel from the adjacent groups; and each of said plurality ofunit pixels comprises a switching element connected to one of said videosignal lines, at least a pixel electrode connected to said switchingelement, at least a counter electrode connected to one of said countersignal lines so that a light transmittance of said liquid crystaldisplay device is changed by an electric field generated between saidpixel electrode and said counter electrode, said electric field having acomponent substantially parallel to the surface of said liquid crystallayer.
 14. A liquid crystal display device according to claim 13,wherein the unit pixels having said one of said video signal linespassing through the center thereof each have a counter electrode and apixel electrode formed on both sides of the video signal line andextended in a column-direction.
 15. A liquid crystal display deviceaccording to claim 14, wherein at least two counter electrodes areconnected to one of said counter signal lines in each of said unitpixels, and said video signal lines are positioned between two counterelectrodes in adjoining unit pixels.
 16. A liquid crystal display deviceaccording to claim 13 or 15, wherein three adjoining unit pixelsselected from the adjacent groups of row-direction arrayed unit pixelsare arranged to straddle the adjacent groups and are assigned threeprimary colors respectively.
 17. A liquid crystal display devicecomprising:a pair of substrates, at least one of which is transparent; aliquid crystal layer interposed between said pair of substrates; atleast one polarizer in optical relationship with said liquid crystallayer; scan signal lines formed in a row-direction over one substrate ofsaid pair of substrates; counter signal lines formed in a row-directionover said one substrate; video signal lines formed over said onesubstrate and crossed by said scan signal lines with an insulating layertherebetween, each of said video signal lines including at least firstand second electrically connected portions, wherein said first portionsextend in a column-direction, and said second portions extend in arow-direction between said scan signal lines and said counter signallines in a plan view; a plurality of unit pixels formed by adjoiningsaid video signal lines and said scan signal lines, said scan signallines each common to one group of row-direction arrayed unit pixels ofsaid plurality of unit pixels, said counter signal lines each common toone group of row-direction arrayed unit pixels of said plurality of unitpixels, and said video signal lines each common to one group ofcolumn-direction arrayed unit pixels of said plurality of unit pixels;wherein the groups of row-direction arrayed unit pixels are eachstaggered one-half pitch of the unit pixels from the adjacent groups;each of said plurality of unit pixels comprises a switching elementconnected to one of said video signal lines, at least a pixel electrodeconnected to said switching element, at least a counter electrodeconnected to one of said counter signal lines so that a lighttransmittance of said liquid crystal display device is changed by anelectric field generated between said pixel electrode and said counterelectrode, said electric field having a component substantially parallelto the surface of said liquid crystal layer; and wherein each of saidsecond portions of video signal lines is separated with a space fromsaid scan signal lines and said counter signal lines in a plan view. 18.A liquid crystal display device comprising:a pair of substrates, atleast one of which is transparent; a liquid crystal layer interposedbetween said pair of substrates; at least one polarizer in opticalrelationship with said liquid crystal layer; scan signal lines formed ina row-direction over one substrate of said pair of substrates; countersignal lines formed in a row-direction over said one substrate; videosignal lines formed over said one substrate and crossed by said scansignal lines with an insulating layer therebetween, each of said videosignal lines including at least first and second electrically connectedportions, wherein said first portions extend in a column-direction, andsaid second portions extend in a row-direction between said scan signallines and said counter signal lines in a plan view; a plurality of unitpixels formed by adjoining said video signal lines and said scan signallines, said scan signal lines each common to one group of row-directionarrayed unit pixels of said plurality of unit pixels, said countersignal lines each common to one group of row-direction arrayed unitpixels of said plurality of unit pixels, and said video signal lineseach common to one group of column-direction arrayed unit pixels of saidplurality of unit pixels; wherein the groups of row-direction arrayedunit pixels are each staggered one-half pitch of the unit pixels fromthe adjacent groups; each of said plurality of unit pixels comprises aswitching element connected to one of said video signal lines, at leasta pixel electrode connected to said switching element, at least acounter electrode connected to one of said counter signal lines so thata light transmittance of said liquid crystal display device is changedby an electric field generated between said pixel electrode and saidcounter electrode, said electric field having a component substantiallyparallel to the surface of said liquid crystal layer; and wherein atleast two counter electrodes are connected to one of said counter signallines in each of said unit pixels, and said first portions of said videosignal lines are positioned between two counter electrodes in adjoiningunit pixels.
 19. A liquid crystal display device according to claim 18,wherein at least said counter electrodes and said pixel electrode extendin a column-direction.
 20. A liquid crystal display device comprising:apair of substrates, at least one of which is transparent; a liquidcrystal layer interposed between said pair of substrates; at least onepolarizer in optical relationship with said liquid crystal layer; scansignal lines formed in a row-direction over one substrate of said pairof substrates; counter signal lines formed in a row-direction over saidone substrate; video signal lines formed over said one substrate andcrossed by said scan signal lines with an insulating layer therebetween,each of said video signal lines including at least first and secondelectrically connected portions, wherein said first portions extend in acolumn-direction, and said second portions extend in a row-directionbetween said scan signal lines and said counter signal lines in a planview; a plurality of unit pixels formed by adjoining said video signallines and said scan signal lines, said scan signal lines each common toone group of row-direction arrayed unit pixels of said plurality of unitpixels, said counter signal lines each common to one group ofrow-direction arrayed unit pixels of said plurality of unit pixels, andsaid video signal lines each common to one group of column-directionarrayed unit pixels of said plurality of unit pixels; wherein the groupsof row-direction arrayed unit pixels are each staggered one-half pitchof the unit pixels from the adjacent groups; each of said plurality ofunit pixels comprises a switching element connected to one of said videosignal lines, at least a pixel electrode connected to said switchingelement, at least a counter electrode connected to one of said countersignal lines so that a light transmittance of said liquid crystaldisplay device is changed by an electric field generated between saidpixel electrode and said counter electrode, said electric field having acomponent substantially parallel to the surface of said liquid crystallayer; and wherein the column-direction arrayed unit pixels areconnected through thin film transistors to the associated video signalline and are arranged on each side of the video signal line alternately.21. A liquid crystal display device according to claim 17, 18, 19 or 20,wherein three adjoining unit pixels selected from the adjacent groups ofrow-direction arrayed unit pixels are arranged to straddle the adjacentgroups and are assigned three primary colors respectively.